All-composite freight trailer in production at U.S. manufacturing facility
By Staff | April 01, 2004
Since the first Compositrailer rolled off the production line in December 2003, Martin Marietta Composites Inc. (MMC, Raleigh, N.C., U.S.A.), has continued development of the all-composite 48-ft "big rig" cargo trailer. Originally developed in Belgium by Compositrailer N.V., Compositrailer is a live-floor transfer trailer (meaning a reciprocating slat conveyor moves to the rear to help discharge bulk cargo, such as solid waste). The trailer's floor, sides, roof, cargo doors and chassis are constructed of fiberglass/vinyl ester composites (only the kingpin, the landing gear, axles, wheels and brakes are made with conventional materials). The unit weighs 25 percent less than a comparably sized metal trailer, and its combination of low weight, corrosion resistance and durability is expected to significantly reduce capital and operating costs for freight haulers. Additionally, the reduction in empty vehicle weight allows carriers to load additional freight and remain within U.S. federal gross vehicle weight limitations.
Source: MMC
MMC manufactures Compositrailer under license to Compositrailer N.V. in its new 185,000 ft² plant located in Sparta, N.C. The trailer parts are made with a combination of pultrusion and filament winding (as described in "Engineering Insights," CT February 2003, p. 36). Pultruded components are provided by Creative Pultrusions Inc. (Alum Bank, Pa., U.S.A.) and Top Glass (Milan, Italy). Base materials include glass fabrics from Vectorply Corp. (Phenix City, Ala., U.S.A.), polyester and urethane resins from Reichhold Inc. (Research Triangle Park, N.C., U.S.A.) and adhesives from Ashland Specialty Chemical Co. - Specialty Polymers and Adhesives (Columbus, Ohio, U.S.A.).
"Interest in commercial trailers and other products has consistently risen since our first delivery," says MMC vice president and general manager Grant Godwin. The company has developed and begun to market a range of trailers up to 57 ft in length, both live floor and tipper models (where the entire trailer is lifted by a hydraulic ram). The initial trailer was produced for the Solid Waste Authority of West Palm Beach, Fla., U.S.A., and other customers have come from Illinois and California, says Godwin.
MMC also has penetrated the commercial rail market with engineered insulated liner panels for refrigerated rail cars, as well as end-wall panels, plenums, and roof/floor components. In addition, it has manufactured a prototype composite truck body on a conventional chassis in anticipation of market demand. The company's composite bridge deck manufacturing operations have been moved to the Sparta facility as well, and several major projects are underway. Lastly, MMC is putting into place the manufacturing capability for producing reinforced panel products "with a new, fully-integrated process," for all of its infrastructure and transportation product lines, according to Godwin.
